Customized footwear and process for manufacturing such footwear

ABSTRACT

An article of footwear for distributing pressure evenly on various regions of the foot comprising an upper and at least one moldable foam piece attached to an inner surface of the upper is provided, together with an article of footwear manufactured by a process comprising attaching at least one moldable foam piece to the inner surface of the upper of the footwear and stretching the upper over a footwear last comprising at least one cavity cut into the surface of the last that accommodates the moldable foam piece.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent ApplicationNo. 60/614,068, filed Sep. 29, 2004.

FIELD OF INVENTION

The present invention relates to footwear. In particular, this inventionrelates to a design, construction, and process of manufacturing forfootwear that better supports and stabilizes the skeletal structure ofthe feet.

BACKGROUND OF THE INVENTION

Most types of climbing footwear are generally designed to fit verysnugly around the toes and heel of the foot. This type of snug designallows efficient transfer of power and energy from the human body torock or ice surfaces. However, the snug design often forces the toesinto a curled or knuckled position. In order to hold the foot in thecurled or knuckled position, the footwear must exert pressure onto thetop portion of the toes, under the ball of the foot, and the back andupper portions of the heel. Due to the differences in individual footshapes, the pressure exerted by the footwear on the toes and heel, aswell as under the ball of the foot, can be quite uncomfortable andsometimes painful, which can affect a climber's performance.

One type of footwear known in the art is manufactured with a set shapeand support, provided with moldable materials. However, the shape andsupport of this type of footwear cannot be modified and therefore thefootwear cannot be formed to the foot. Another type of footwear ismanufactured with a thermoplastic structure throughout the upper of thefootwear. The thermoplastic structure can be heated and molded to thefoot. However, the thermoplastic structure is typically bulky and heavy,and has limited rigidity, and the moldability of the footwear is limitedto the upper portion. Yet another type of footwear is provided with aself-contained bladder within the footwear. Different types ofmaterials, such as “gel” or foam pieces, are contained within thebladder. A major limitation of this type of footwear is that the bladderis generally not integrated into the main structure of the footwear viamutual composite linkage or mechanical attachment. Also, theself-contained bladder system can only achieve one set of stiffnessafter molding, which leaves no customization of desired support.Therefore, the footwear cannot be customized to the feet. Still anothertype of footwear is provided with bladder systems that can be injectedexternally with a stiffening agent.

Most types of footwear known in the art are manufactured around a last.Generally, a footwear manufacturing process first involves stretchingthe upper of the footwear around the last using a considerable amount oftension. For example, in cement lasted footwear designs, the upper isstretched over the last using a lasting machine which applies a highamount of tension to the upper in order to stretch it over the last andto glue the edges of the upper to material on the bottom of the last.During this process, if a moldable foam piece is attached to the insidesurface of the footwear upper, the foam becomes and remains compressed,thereby losing its moldable properties.

U.S. patent Publication No. US20040049950 discloses moldable footwearprovided with a base and an upper portion. The upper portion containstwo bladders located on the medial and lateral side of the foot. The twobladders are placed approximately between the base and malleoli, andbetween the middle of the heel and the proximal metatarsals. Thebladders contain a dry composite. The dry composite is impregnated witha fast setting resin/hardener liquid that is dispensed via a doublebarrel syringe and spiral cap through a small opening located on theposterior heel.

U.S. patent Publication No. US20050144034 discloses a process formanufacturing injection molded polyurethane footwear consisting of twoor more parts with different compositions. The process is directed tosimultaneously injecting two different formulas of polyurethane into twodifferent cavities of the same mold. The dual rotating or shufflingsole-plate makes it possible to inject the outsole and theinsole/upper/shaft simultaneously without mixing.

U.S. patent Publication No. 20030227105 discloses an article oftextile-soled footwear and process of manufacturing the footwear byemploying a fabrication process and an apparatus that allows fabricationof the footwear's outer shell via a single injection-molding step. Thearticle of footwear is provided with a textile layer at theground-contacting surface of the outsole, the textile layer beingmoldably and integrally attached, in a common mold, to the moldedoutsole as it is being created during the injection process. Fastenersare set along the side of the sole plate of the injection mold to securethe textile layer across the sole plate, preventing the textile layerfrom being moved during injection of the moldable compound to form theoutsole. The sole plate and the sidewalls of the injection mold areassembled in place for the injection process. The shoe upper is fittedonto the shoe last and set in place in the mold, the mold is closed, andthe moldable compound is injected into the mold. Once injection iscomplete, the mold side walls are opened, the injected shoe is removed,and the excess textile layer is trimmed.

U.S. Pat. No. 6,228,300 and U.S. patent Publication No. 20010004139 bothdisclose moldable footwear which conforms to the size and shape of thefeet, together with a process of forming the footwear. The process inaccordance with the above disclosures comprises molding the startingmaterial on and around a foot, wetting the material with a mixturecomprising a leather stiffening or hardening agent, and drying thewetted material while still on the foot.

U.S. Pat. No. 4,886,238 discloses a molding apparatus and a process foruse in the manufacture of an article of footwear by molding an insole ofmolten flexible plastic material to a preformed outsole and to an upper.

U.S. Pat. No. 4,535,554 discloses an article of footwear formed of amolded plastic body member, provided with a molded plastic foot supportmember that supports the wearer's foot, and a flexible harness whichretains the body member on the wearer's foot. The body member has a soleportion, a toe cup, a heel cup, and longitudinal sidewalls which extendfrom the toe cup to the heel cup. The foot support member has an uppersurface, located at about the same height as the upper edges of thesidewalls, which provides anatomical support for a wearer's foot. Theharness has a horizontal strap and inclined straps. The horizontal strapis connected to the heel cup, and the inclined straps are connected tothe sidewalls of the body member.

The various types of footwear and various processes for manufacturingthe footwear described above do not adequately provide for evendistribution of pressure on various regions of the wearer's foot. Inaddition, the footwear and the processes described above do notadequately prevent moldable materials that are attached to the upper andthe insole of the footwear from being compressed during the process offitting the upper or insole of the footwear to a footwear last. It istherefore desirable to provide an article of footwear and a process formanufacturing such footwear to overcome the aforementioned disadvantagesand problems

SUMMARY OF THE INVENTION

An article of footwear is provided for distributing pressure evenly onthe top portion of the toes, the instep region of the foot, the upperankle region, the back and lower region of the heel, and the regionunder the ball of the foot.

In one embodiment, the upper of the inventive footwear is provided withat least one moldable foam piece attached to an inner surface of thefootwear upper in at least one of an upper toe region, an instep regionof the foot, an upper ankle region, and a back and lower region of theheel.

In another embodiment, the insole of the inventive footwear is providedwith at least one moldable foam piece attached to an inner surface ofthe insole in a region under the ball of the foot. As used herein and inthe claims, the term “insole” means a flexible layer that is positionedbetween the wearer's foot and a midsole and/or an outsole of thefootwear. The inner surface of the insole faces the midsole and/oroutsole and the outsole contacts the ground.

Alternatively, the inventive footwear is provided with a first moldablefoam piece attached to an inner surface of the insole in a region underthe ball of the foot and a second moldable foam piece attached to aninner surface of the footwear upper in at least one of an upper toeregion, an instep region of the foot, an upper ankle region, and a backand lower region of the heel.

The upper of the footwear may be constructed of an inelastic materialand the moldable foam is typically a closed-cell expanded foam. Themoldable foam piece may be in any desired thickness and density. Themoldable foam piece may be in any configuration and is provided with agenerally tapered outer edge in a manner such that when the moldablefoam piece is attached to the inner surface of the upper or insole, theouter edge of the moldable foam piece forms an obtuse angle with respectto the inner surface of the upper or insole. Thus, the moldable foampiece has a convex configuration, like the surface of a sphere. Inaddition, the surface contour of the moldable foam piece can besymmetrical or asymmetrical with respect to the perimeter of themoldable foam piece.

In another embodiment, the inventive footwear is provided with at leasttwo pull tabs attached to the Achilles notch area of the upper heelcounter of the footwear and positioned on opposing sides of the heelcounter.

A process of manufacturing the inventive footwear is also provided. Inone embodiment of the inventive process, at least one moldable foampiece is molded into a customized configuration by the application ofheat and pressure or pressure alone. After the desired customizedconfiguration is achieved, the at least one moldable foam piece isattached to the inner surface of either the upper or the insole of theinventive footwear.

The upper or the insole, to which the at least one moldable foam pieceis attached, is stretched over a specially designed last. The lastcomprises at least one cavity or depression cut into the surface of thelast. The at least one cavity is hollowed-out and basin-like, and has agenerally concave and rounded configuration, resembling the insidesurface of a sphere. The at least one cavity has a larger surface areathan that of the moldable foam piece. This allows the moldable foampiece to remain uncompressed during the manufacturing process when theupper or the insole of the inventive footwear is stretched over theinventive last, thus providing the footwear with curved protrusions onthe inside. After the upper is stretched over the inventive last, it isattached or bonded to a rand, a midsole and/or an outsole, using amethod known in the art.

When the inventive footwear is worn and tightened by laces, straps, orelastic bands, the moldable foam attached to the inner surface of theupper and/or the insole of the footwear is compressed against regions ofthe foot that exert the highest pressure against the inner surface ofthe footwear, and/or against natural depressions in the foot, such as inthe upper ankle area, thus creating an inside contour that matches thecontour of the wearer's foot. The matching of the shape of the inventivefootwear to the wearer's foot not only allows for distribution ofpressure, but also relieves various pressure points, resulting inimproved comfort for the wearer's feet.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the present invention are described in detailbelow and illustrated in the drawings, in which:

FIG. 1 shows a top view of an embodiment of the inventive footwear last;

FIG. 2 shows a bottom view of another embodiment of the inventivefootwear last;

FIG. 3 shows a side view of yet another embodiment of the inventivefootwear last;

FIG. 4 shows a side view of still another embodiment of the inventivefootwear last;

FIG. 5 shows a side view of an alternative embodiment of the inventivefootwear last;

FIG. 6 shows a top view of another alternative embodiment of theinventive footwear last; and

FIG. 7 shows a perspective view of an embodiment of the inventivefootwear provided with two moldable foam pieces as indicated by dottedlines.

DETAILED DESCRIPTION OF THE INVENTION

An article of footwear is provided having improved distribution ofpressure on the top region of the toes, over the instep of the foot, onthe upper region of the ankle, the back and lower region of the heel,and/or the region under the ball of the foot by custom molding theinterior surface of the inventive footwear to the foot. This isaccomplished by providing curved projecting volumes, or protrusions, oninterior surfaces of the footwear in regions where the foot exerts highpressure against the interior surfaces of the footwear and/or in regionsthat match natural depressions or cavities in the foot, therebyproducing footwear that provides better fit and more even distributionof pressure. More specifically, the protrusions, which are preferablyformed of moldable foam pieces, are provided in at least one of thefollowing regions: the upper toe region, the instep region, the upperankle region, the back and lower region of the heel, and the regionaround the ball of the foot. The inventive footwear is capable ofwithstanding wear and tear, and of holding the foot in the optimalposition for efficient transfer of power and energy. The presentinvention may be applied to various forms of footwear including, but notlimited to, climbing, athletic, hiking, mountaineering, casual, dressshoes, sandals, slippers, clogs, and the like.

An embodiment of the inventive footwear 20 is shown in FIG. 7. The upper14 of the footwear 20 is provided with at least one moldable foam piece30 attached to an inner surface of the footwear upper 14 in an upper toeregion 40. In other embodiments, the at least one moldable foam piece 30may be attached to an instep region 50 of the foot, an upper ankleregion 60, a back and lower region of the heel 70, or combinationsthereof.

In another embodiment, an insole 80 of inventive footwear 20 is providedwith at least one moldable foam piece 30 attached to an inner surface ofinsole 80 in a region under the ball of the foot. As used herein and inthe claims, the term “insole” means a flexible layer that is positionedbetween the wearer's foot and a midsole and/or an outsole of thefootwear. The inner surface of the insole faces the midsole and/oroutsole and the outsole contacts the ground.

Alternatively, inventive footwear 20 may be provided with a firstmoldable foam piece 30 attached to the inner surface of insole 80 in aregion under the ball of the foot and at least one additional moldablefoam piece 30′ attached to the inner surface of footwear upper 14 in atleast one of the upper toe region 40, instep region 50, upper ankleregion 60, and back and lower region of the heel 70.

Inventive footwear 20 may be provided with at least two pull tabs 100attached to an Achilles notch area 120 of an upper heel counter of thefootwear 20 and positioned on opposing sides of the heel counter. Thepull tabs 100 may also take form of loops.

If upper 14 of footwear 20 is constructed of mostly elastic material, itis difficult to maintain the desired shape of the foot within thefootwear 20. Therefore, upper 14 of inventive footwear 20 comprises aninelastic material so that the footwear 20 is capable of holding thefoot in the optimal position for efficient transfer of power and energy.Examples of the inelastic material include, but are not limited to,leather, synthetic leather, woven fabrics, and the like.

Moldable foam piece 30 is typically a closed-cell expanded foam, such asethylene vinyl acetate (EVA), polyurethane, or Pebax® foam. Moldablefoam piece 30 may be constructed in any desired thickness and density.In one embodiment, moldable foam piece 30 is between about 6 mm to 10 mmin thickness and has a durometer measurement between about 20 to 40 on aShore C scale. In areas where the foot is more sensitive to pressure,such as the toes, a lower density foam may be used, for example, 25 on aShore C scale. A higher density foam may be used in and around the heelarea, where the foot is less sensitive to pressure and the forces on thesides of the footwear are greater, and a firmer foam, for example, 35 ona Shore C scale.

Moldable foam piece 30 may be in any configuration and it may generallyhave an oval or oblong configuration. Moldable foam piece 30 is providedwith a generally tapered outer edge 150 in a manner such that whenmoldable foam piece 30 is attached to the inner surface of upper 14, forexample, outer edge 150 of moldable foam piece 30 forms an obtuse anglewith respect to the inner surface of upper 14. Thus, moldable foam piece30 generally has a convex configuration with respect to the innersurface of upper 14 and resembles the surface of a sphere. In addition,the surface contour of moldable foam piece 30 can be symmetrical orasymmetrical with respect to the perimeter of moldable foam piece 30.

A process of manufacturing the inventive footwear is also provided. Mostfootwear is manufactured around a last. Generally, a footwearmanufacturing process first involves the stretching of the upper of thefootwear around the last with a considerable amount of tension. Inclimbing shoes, for example, rubber rands and outsole are then bonded orglued to the upper of the footwear. The rand and outsole bonding processalso requires applying considerable pressure and tension to the upper ofthe footwear. In cement lasted footwear designs, the upper is stretchedover the last using a lasting machine which applies a high amount oftension to the upper in order to stretch it over the last and to gluethe edges of the upper to material onto the bottom of the last. Inaddition, heat is sometimes used to help cure the glue. During thisprocess using a conventional last, if a moldable foam piece is attachedto the inside surface of the footwear upper, the foam will becomecompressed and remain compressed, thereby losing its moldableproperties.

During the process of manufacturing the inventive footwear, a speciallydesigned last having at least one cavity or depression cut into thesurface of the last is employed. The cavity accommodates the moldablefoam piece and thereby allows the moldable foam piece to remainuncompressed during the manufacturing process. The upper may thus belasted, and the rands and the soles bonded to the upper of the footwearusing all necessary pressure and heat without compressing the moldablefoam piece.

In one embodiment of the inventive process, at least one moldable foampiece 30 may be molded into a customized configuration quickly, ifdesired, by utilizing heat and pressure. Alternatively, moldable foampiece 30 may be molded into a customized configuration slowly byutilizing pressure alone.

After the desired customized configuration of moldable foam piece 30 isachieved, an untrimmed piece of moldable foam is attached to the linerof upper 14 or insole 80 of the inventive footwear. The liner offootwear 20 and moldable foam piece 30 are generally laminated to eachother. In one embodiment, the liner and the untrimmed moldable foam areperforated. The perforations, generally about 3 mm in diameter andapproximately 6 mm apart, pass through both the liner layer and theuntrimmed moldable foam. The perforated liner and the untrimmed moldablefoam are then trimmed, for example, approximately to the shape of upper14 of footwear 20. The edges of the liner and the trimmed moldable foamare next skived and laminated to upper 14. The liner and the moldablefoam are then attached to the bottom front portion and the top edge ofthe footwear 20, by way of stitching, sewing, bonding, or gluing.

The upper 14 or the insole 80, to which at least one moldable foam piece30 is attached, is stretched over the specially designed last. Anembodiment of the inventive last 10 is shown in FIG. 1. The last 10comprises at least one cavity 12 or depression cut into the surface ofthe last 10. The at least one cavity 12 is hollowed-out and basin-like,and has a generally concave and rounded configuration, resembling theinside surface of a sphere. The at least one cavity 12, generally has alarger surface area than that of moldable foam piece 30, allowingmoldable foam piece 30 to remain uncompressed during the manufacturingprocess when the upper 14 or the insole 80 of the inventive footwear 20is stretched over the inventive last 10.

FIG. 1 shows an embodiment of inventive last 10 provided with twocavities 12 about the upper toe region 40. FIG. 2 shows anotherembodiment of inventive last 10 provided with a cavity 16 about theregion under the ball of the foot 90. FIG. 3 shows yet anotherembodiment of inventive last 10 provided with cavity 12 about the uppertoe region 40 and a cavity 25 about the upper and back heel region 70.FIG. 4 shows still another embodiment of inventive last 10 provided withcavity 12 about the upper toe region 40, cavity 25 about the upper andback heel region 70, and a cavity 16 about the region under the ball ofthe foot 90. FIG. 5 shows an alternative embodiment of inventive last 10provided with cavity 12 about the upper toe region 40, cavity 16 aboutthe region under the ball of the foot 90, and a cavity 35 about theupper ankle region 60. FIG. 6 shows another alternative embodiment ofinventive last 10 provided with two cavities 45 about the instep region50.

Inventive footwear 20 may be manufactured by a process comprisingstretching upper 14 over last 10 provided with at least one cavity 12about the upper toe region 40. When upper 14 of the inventive footwearis stretched over last 10, moldable foam piece 30, which is attached tothe inside of upper 14, corresponds to and fits within the basin-likecavity 12 of last 10. The concave configuration of cavity 12 allowsmoldable foam piece 30 to retain a tapered outer edge 150.

Inventive footwear 20 may also be manufactured by a process comprisingstretching insole 18 over last 10 provided with at least one cavity 16cut into the bottom of footwear last 10, about the region around theball of the foot 90. In this embodiment, moldable foam piece 30 isskived all the way around the perimeter of last 10 and is attached orbonded to insole 18 of footwear last 10. Insole 18 and moldable foampiece 30 are then bonded upper 14 of the inventive footwear 20 whereinmoldable foam piece 30 is inserted between insole 18 and upper 14 offootwear 20.

Inventive footwear 20 may yet be manufactured by a process comprisingstretching upper 14 over last 10 provided with at least one cavity 25cut into a back heel area 70 of last 10 in a shape similar to anAchilles pad, centered at the back heel area 70 of footwear last 10.Moldable foam piece 30 is skived all the way around the perimeter ofback heel area 70 and is bonded to back heel area 70 of footwear last10. The Achilles pad shaped cavity 25 is then finished with a finishingmaterial. The finishing material includes, but not limited to, pig skin,a thin and supple synthetic material, and the like.

Inventive footwear 20 may still be manufactured by a process comprisingstretching upper 14 over last 10 provided with at least one cavity 35cut into an upper ankle region 60 of last 10. Moldable foam piece 30 isskived all the way around the perimeter of an upper ankle region 60 andis bonded to upper ankle region 60 of footwear last 10.

Inventive footwear 20 may alternatively be manufactured by a processcomprising stretching upper 14 over last 10 provided with at least onecavity 45 cut into an instep region 50 of footwear last 10. Moldablefoam piece 30 is skived all the way around the perimeter of instepregion 50 of footwear last 10 and is bonded to instep region 50 offootwear last 10.

Further, inventive footwear 20 may be manufactured by a processcomprising inventive last 10 provided with at least one cavity 12,cavity 16, and cavity 25 cut into various regions of footwear last 10.In other alternative embodiments, inventive footwear 20 may bemanufactured by a process comprising last 10 provided with at least onecavity 12, cavity 16, cavity 25, at least one cavity 35, and at leastone cavity 45 cut into various regions of footwear last 10.

The present invention has been described with reference to specificembodiments. These specific embodiments should not be construed aslimitations on the scope of the invention, but merely as illustrationsof exemplary embodiments. It is further understood that manymodifications, additions and substitutions may be made to the describedfootwear and process of manufacturing such footwear without departingfrom the broad scope of the present invention.

1. An article of footwear comprising: an upper; an insole; and at leastone moldable foam piece attached to an inner surface of either the upperor the insole, wherein when a user's foot is inserted in the footwear,the moldable foam piece is positioned in a region where the foot exertshigh pressure against an inner surface of the footwear.
 2. An article offootwear comprising: an upper; an insole; and at least one moldable foampiece attached to an inner surface of either the upper or the insole,wherein the moldable foam piece is located in a region selected from thegroup consisting of: top region of the toes, instep of the foot, upperregion of the ankle, back and lower region of the heel, and under theball of the foot.
 3. The article of footwear of claim 2, wherein theupper is constructed of an inelastic material selected from the groupconsisting of: leather, synthetic leather, woven fabrics, and the like.4. The article of footwear of claim 2, wherein the moldable foam piecehas a thickness between 6 and 10 mm.
 5. The article of footwear of claim2, wherein the moldable foam piece has a density thickness between 20and 40 on the Shore C scale.
 6. The article of footwear of claim 2,wherein the moldable foam piece comprises a generally tapered outer edgein a manner such that when the moldable foam piece is attached to theinner surface of the upper or the insole, an outer edge of the moldablefoam piece forms an obtuse angle with respect to the inner surface ofthe upper or the insole.
 7. The article of footwear of claim 2, whereinthe moldable foam piece is symmetrical with respect to the perimeter ofthe moldable foam piece.
 8. The article of footwear of claim 2, whereinthe moldable foam piece is asymmetrical with respect to the perimeter ofthe moldable foam piece.
 9. The article of footwear of claim 2, whereinthe moldable foam piece is a closed-cell expanded foam selected from thegroup consisting of: ethylene vinyl acetate (EVA), polyurethane, orPebax® foam.
 10. The article of footwear of claim 2, wherein thefootwear is provided with at least two pull tabs attached to an Achillesnotch area of the footwear.
 11. A method of manufacturing an article offootwear comprising: attaching at least one moldable foam piece to aninner surface of an upper of the footwear; stretching the upper over afootwear last comprising at least one cavity cut into the surface of thelast that accommodates the moldable foam piece; and skiving the moldablefoam piece around the perimeter of the at least one cavity, wherein themoldable foam piece remains uncompressed when the upper of the footwearis stretched over the last.
 12. An article of footwear manufactured bythe method of claim
 11. 13. The method of claim 11 wherein the at leastone cavity is cut into a region of the footwear last selected from thegroup consisting of: an upper toe region, an instep region, an lowerankle region, a back and lower region of the heel, and combinationsthereof.
 14. An article of footwear manufactured by the method of claim13.
 15. A method of manufacturing an article of footwear comprising:attaching at least one moldable foam piece to an inner surface of aninsole of the footwear; stretching the insole over a footwear lastcomprising at least one cavity cut into the surface of the last thataccommodates the moldable foam piece; and skiving the moldable foampiece around the perimeter of the at least one cavity, wherein themoldable foam piece remains uncompressed when the insole of the footwearis stretched over the last.
 16. An article of footwear manufactured bythe method of claim
 15. 17. The method of claim 15, wherein the at leastone cavity is cut into of the footwear last about a region under theball of the foot.
 18. An article of footwear manufactured by the methodof claim 17.